I've flown three trips of 5.0 to 5.5 air hours: Boston to Chicago
Midway (760 nm); Wichita to Scottsdale (760 nm); and West Yellowstone to Duluth
(890 nm). The longest distance trip I've ever flown was from Des Moines to
White Plains, NY (920 nm) in 4.3 hours, but that was with tailwinds of 50-73
The five hour trips were flown LOP (there's no other way to get that kind of range) and in each instance I landed with at least 1.5 hours of fuel (which is my personal minimum). The Boston to Chicago trip had a 20-30 knot headwind the entire way, plus a 15 minute hold in Indiana due to traffic at Midway; the other two trips had negligible winds.
My plane is an SR22 built in April 2003, so it doesn't have the improvements available in the G2s. Nonethelss, it still goes far and fast.